<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <label>表单</label>
    <form action="a.html">
        文本框：<input type="text" value="abc" name="username"/><br/>
        <label for="textfield">文本框：</label><input id="textfield" type="text"/><br/>
        密码框：<input type="password" value="123" name="password"/><br/>
        文本域：<textarea rows="10" cols="20">abcd</textarea><br/>
        单选按钮：<input type="radio" name="sex" value="1"/>男
                <input type="radio" name="sex" value="0"  checked="checked"/>女<br/>
        下拉列表：<select name="s">
                    <option>---请选择---</option>
                    <option value="1">aaa</option>
                    <option value="2" selected="selected">bbb</option>
                    <option value="3">ccc</option>
                </select>
                <select>
                    <optgroup label="aaaa">
                        <option>aaa</option>
                        <option>bbb</option>
                        <option>ccc</option>
                    </optgroup>
                    <optgroup label="bbbb">
                        <option>ddd</option>
                        <option>eee</option>
                    </optgroup>
                </select><br/>
        复选框：<input type="checkbox" name="hobbies" value="1" checked="checked"/>吃
               <input type="checkbox" name="hobbies" value="2"/>玩
               <input type="checkbox" name="hobbies" value="3" checked="checked"/>睡<br/>
        文件：<input type="file" name="file"/><br/>
        <!-- 隐藏表单 -->
        <input type="hidden" name="id" value="11"/>
        <input type="submit" value="提交"/>
        <input type="reset" value="重置"/>
        <input type="button" value="按钮" onclick="alert('Hello');"/>
        <button>按钮</button><br/>
        <input type="color" name="c"/>
        <input type="date"/>
        <input type="datetime"/>
        <input type="datetime-local"/>
        <input type="email"/>
        <input type="month"/>
        <input type="number"/>
        <input type="range"/>
        <input type="search"/>
        <input type="tel"/>
        <input type="time"/>
        <input type="url"/>
        <input type="week"/>
    </form>
    <button>按钮</button>
</body>
</html>